Carbon gland



C. A. PARSONS, S. S. COOK AND L. M. DOUGLAS.

CARBONGLAND. APPLICATION FILED JULY 19,1919.

1,331,362. Patented Feb. 17. 1920.

Fig.1.

C d/ k e d NVENT R UNITED STATES PATENT OFFICE.

CHARLES ALGERNON PARSONS, STANLEY SMIlI-I COCK, AND LOUIS MORTIMERDOUGLAS, OF NEXVCASTLE-UPON-TYNE. ENGLAND; SAID COOK AND SAID DOUGLASASSIGNORS TO SAID PARSONS.

CARBON GLAND.

Specification of Letters Patent.

Patented Feb. 17, 1920.

Original application filed October 5, 1918, Serial No. 257,680.EZ-ivided and this application filed July 19, 1919. Serial No. 312,055.

To all whom it may concern.

Be it known that we, CHAnLns ALGERNON PARSONS, K. C. 13., STANLEY SMITHCoon, and Loors MORTIMER DOUGLAS, all subjects of the King of GreatBritain and Ireland, and all residing at Heaton lVorks,hewcastle-upon-Tyne, in the county of Northuniberland, England, haveinvented certain new and useful Improvements in Carbon Glands, of whichthe following is a specification.

This invention relates to carbon glands for packing rotating shafts andhas for its object to produce a carbon gland-ring capable of sustaininghigher pressures than have been hitherto carried and having greatlyreduced friction while being more reliable than has hitherto been thecase with such gland-rings.

The invention is more particularly concerned with the type of gland-ringdescribed in our co-pending application ITO. 257080 from which this is adivisional application.

Carbon glands as heretofore designed consist of rings, each ring beingmade up of sectors of graphitic carbon usually of rectangular crosssection, embracing the rotating shafts and held together by a springencircling there, the purpose of such carbon gland-ring being to battlethe flow of steam from a higher pressure on one side of it to a lowerpressure on the other. The outer periphery of the gland-ring is in suchcase subjected over its whole area to the hi her pressure, while itsinner periphery, which is in contact with or is bored to fit the surfaceof the shaft, is subject to a lower av rage pressure owing to the fallof pressure from the high pressure side to the low pressure side. Itfollows, therefore, that there is a radial inward force on the ringpressing it toward the shaft, thus giving rise to friction, absorbingpower and producing a corresponding amount of heat.

The present invention consists broadly in constructing gland-rings insuch a manner that they are substantially in radial equilibrium underthe steam pressure.

The invention further consists in forming the gland-rings of L shapewith the extension along the shaft toward the low pressure side, a spacebeing provided between the back of the extended portion and the housingof the gland-ring, which space is exposed to the lower pressure.

The invention also consists in an internal projection so disposed thatthe end of the extension of the gland ring bears against it in order toprevent tilting of the se 'inents.

The invention still further consists in constructing the internalprojection as a second carbon or like ring placed in the same groove ofthe housing as the gland ring itself.

The invention also consists in the improved carbon glands hereinafterdescribed.

In carrying the invention into effect ac cording to the exampleillustrated in Fig. 1, the gland is made up of a number of L shapedsegments a with extensions a lying along the shaft toward the lowpressure side. A space I) is allowed between the housing of the glandand the back of the extended portion of each carbon sector, and

this space is exposed to the low pressure. In this manner whileretaining the same width of ring (in an axial direction) as wouldnormally exist in an ordinary ring of rectangular section the inwardpressure of the steam on the gland-ring may be made substantially equalto the outward pressure, there being high pressure over the periphery ofthe gland-ring on the high pressure side'and low pressure over the backof the extension on the low pressure side, these two pressures actingagainst the outward radial pressure which varies along the shaft fromthe higher to the lower value. The rotating shaft is shown at 0 (Z, andc is-the high pressure and (Z the low pressure end.

The housing may be provided with a projection 6 bearing against the endof the extension a, the gland-ring thus fitting closely against thehousing in two planes perpendicular to the axis of the shaft. Anaperture f is provided in the projection 6 against which the end of theextension bears to allow the access of low pressure steam to the spaceZ) at the back of the extension.

Fig. 2 is a modification of Fig. 1 in which a second carbon ring 9 isemployed as a support for the balanced ring a. This second ring, as willbe seen, is bored out clear of the shaft. Owing to the low thermalexpansion of carbon relatively to the metal of the gland housing, thismethod gives an advantage over that shown in Fig. 1, because of theconstancy of the lit of the adjacent transverse faces under varyingtemperatures.

By means of the invention the rings are substantially in equilibrium inthe radial direction under the steam pressure so that friction againstthe shaft is reduced and 4 higher steam pressures across the glandringscan be allowed.

In consequence of the reduced friction.

and reduced heating a more reliable gland is obtained. 3

It is usually preferable to leave a slight balance of pressure in theinward radial direction to assist the encircling spring h in keeping thecarbon sectors in place. This spring may be placed either around theouter periphery of the ring or around the periphery of the extendedportion of the ring. 7

The use of an encircling spring is not essential as the carbon rings maybe held together by any other suitable means.

. Having now described our invention what we claim as new and desire tosecure by Letters Patent is 1. In carbon and like glands forrotatingshafts comprising packing rings divided into segments each with anextension projecting toward the low pressure end of the shaft, aninternal projection so disposed that the end of the extension of thegland ring bears against it in order to prevent tilting of the segments.1

2. In carbon and like glands as set forth in claim 1 a supplementarycarbon or like ring to form the internal projection against which thegland ring bears;

In testimony whereof we have signed our names to this specification.

CHARLES ALGERNON PARSONS. STANLEY SMITH COOK. LOUIS MORTIMER DOUGLAS.

